Rotary-hook sewing-machine.



ITED sTATEs PATENT OF ICE;

MARTIN HEMLEB, 0E ELIZABETH, NEW. JERSEY, AssIGnoE TO THE SIN ER MANUrAo;

TUBING COMPANY, A CORPORATION or NEW JERSEY. V

ROTARY-HOOK SEWING-MACHINE.

To all whom it may concern:

Be it known that I, MARTIN HEMLEB, a citizen of the United States, residing at Elizabeth, in the county of Union'and State of New Jersey, have invented certain new and useful Improvements in Rotary-Hook Sewing-Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to that type of rotary hook sewing machines in which the hook or. loop-taker makes 'a plurality of ro-.

tations to one reciprocation of the needle and has for an object to provide efiective meansfor driving said loop-taker when se-i cured upon a vertical shaft by a connection with the horizontal main or driving 'jshaft. Heretofore such a connection between the main and loop-taker shafts has been effected by employment of an intermediateor lower horizontal shaft, one end of which was con-f,

nected to the loop-taker shaft through a pai'r of speed-multiplying bevel gears. j The opposite end of the intermediate shaft was driven through the usualpitmen connections with a pair of quartered cranks'formed on the main-shaft. The use ofbevel gears 'beneaththe bed-plate is undesirable as they are more or less noisy in operat on and require special housingto provide for proper lubrication and-to prevent introduction of dirt and grit to impair their effectiveness and durability.

- The present invention is designed to obvi- 7 ate theuse of intermeshing gears beneath the bed-plate, to reduce vibration causedby reciprocating or; unbalanced connections,,and to provide a %'light weight mach ne better adapted for high'speed and quiet operationv than those heretofore used;

. According to the present improvement the main-shaft, journaled in the overhangin arm, is connected by speed-multiplying beve gears to an upright shaft journaled' within the hollow brackebarm standard and. provided at. its lower end with angularly, disposed cranks connected pitmen to similar cranks upon the vertical hook-shaft upon' which the loop-seizing member is sewith the usual recip-- cured for cooperation rocating needle.

In the drawings,

Figure 1 is aside elevation of a sewing machine embodying the present improvement with the frame partly Specification of Letters Patent.

Patented 0a. s, 1918.

Application filed October 18, 1916. Serial No. 126,237.

in section, and Fig. 2 of the same.

The frame ofthe machine comprises thel is a bottom plan vview usual bed-plate 1 from which rises vthe'h l- 7 low bracket-armstandard, 2 having the tubular lateral member 3 within which .is

'journaled the main ,or driving shaft 4 hav mg the'usual operative connection with the reciprocating needle-bar 5 carryin the needle 6. I

Depending from the bed-plate l is the bearing bracket 7 in which is journaled the vert1cal loop-taker shaft 8 having secured set-screw (not shown) the hub 14 ofca crank 17 is fixed-upon the lower end of the vertical intermediate'shaft 18which is journaled within the bearing bosses '19 and embraced the standard 2." The crank-studs offthe I s a fts 8. and 18 are connectedby means of the 'pitmen 20 to establishdriving relation between said shafts. The shaft 18 has fixed upon its-upperend the bevel pinion 21 mesh-- 4 1 ing with the bevel gear 22 of double its size fixed upon the main-shaft 4 by which the I intermediate shaft is driven at twice the "speed of the main-shaft, its movements being imparted to the loop-taker shaft through: the described -pitmen connection.

By the means thus described, the speedaccelerating gears 21 and 22 are housed within the'bracket-armwhere they are protected from foreign matter which would impair their efiectivenes's, and the connecvtions with the loop taker shaft beneath the bed-plate are of a pivotal character so' as to exclude lint and gritthrown 'offin the stitching operation while insuring noiselessness'and durability in operation.

It will be noted that the main-shaft .is not I unbalanced by the presence of quartered cranks which in prior constructlons tend to cause excessive vibration of the tubular arm toward and from the operator if high speed operation is attempted. In the present con;

* invention, what I claim herein is 4 In a sewing machine, a frame comprising a bed-plate, hollow standard and bracketarm, a rec1procating needle carried by the.

bra-cketarm,- a needledriving shaft journaled in the bracket-arm, a loop-taker, a loop-taker shaft journaled beneath the bedplate in parallelism with the needle-path, a

pairs of angularly related cranks carried by name to this specification.

the loop-taker shaft and disposed below the bed-plate, and means for driving said looptaker shaft at a uniform angular velocity,

said means including a vertical shaft journaled in said standard and provided beneath the bed-plate with angularly related cranks,'

a driving connection including speed multiplying 'gearing between the needle-driving and vertical shafts, and parallel pitmen disposed horizontally beneath the bed -plate and connecting the cranks of said vertical and loop-taker shafts.

In testimony whereof, I have signed my MARTIN HEMLEB. 

